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Ocean currents

I'm working on a ConWorld for a nationsim game I'm currently programming, that's pretty much based on Earth, and I have a quick question about ocean currents. I generated a world in Fractal Terrains and played around with it a bit, and when I got to a result I as happy with I immediately started adding nations and such. Which turned out to be a bad idea, as I forgot that the area that I want to resemble Europe was placed directly on the world's equator. So I was wondering if playing around with ocean currents could give that particular landmass a Europe-esque climate. (Circled in purple) I've made a map here to check out:

So for one, I was wondering if this is a realistic ocean current situation at all, and then if it would at all help with my climate problem.

I would say that the circled area is not very pleasant: Lies (probalby, I can't really tell the scale) on a tropical, the westcoast has a good chance for a cold current (cold water from the north being sucked towards the equator) and there won't come much moisture from east either. I am sure this area is a desert.

Also, which direction does the world rotate? Is it counterclockwise like the Earth (sun rises in the east, sets in the west)? Or is it clockwise? Rotational direction will play a huge part on where the warm and cold currents will be.

rmfr

Perhaps imagination is only intelligence having fun. - Albert Einstein

A good friend will come down and bail you out of jail. A best friend will be in jail with you and say, "Dude, we screwed up."

Don't know if this will help any at all. Or it might be too much information.

List of Assumptions
1) The map you created shows only the ocean temperatures, thus black is the land.
2) The map shows the entire world.
3) If the map shows the entire world, then you made the map very close to an Equirectangular Projection, being 4318px × 2130px.

I scarfed your map and loaded it into Bryce and projected it onto a sphere to get some global views. I do this all the time when I create world maps in an Equirectangular Projection. Putting the map on a sphere gives me a better idea on the land mass distortion as one approaches the poles in an Equirectangular Projection. I rendered a global view of Nuelan rotated every 30 degrees. Please note that the 000° is arbitrary in Bryce. I used no control on how Bryce pasted the map onto the sphere (other than telling Bryce to apply it in a spherical projection). I used complete defaults in the program, then rotated the Y axis every 30°. Once I had all the renders, I loaded them into a template I have created in Photoshop that will show me the equator, and 30° and 70° north and south latitudes.

The equators are a darkish green. 30° north and south latitudes are yellow. 70° north and south latitudes are cyan.

The equator, and within 10° latitude, shows where the tropical regions exist. The 30° latitudes, both north and south, show where the subtropical high (STH) regions are most likely to form. The STHs are where deserts are most likely to exist. The 70° latitudes (and on to the poles), both north and south show where the arctic regions are most likely to be. Of course, these are only general guidelines, using Earth as a reference. The orbital obliquity of the world will play a large influence on how large or small the artic regions will be. Land masses and ocean currents can and will change these. However, having these guidelines are helpful. Also included are polar projections showing how the map appears on the north and south pole. The choice of north and south were arbitrarily chosen by me. They may not be the same as you may want.

I had to guess where some of the land was where the violet circle was drawn. All mistakes on these guesses are 100% my error. Sorry if I got them wrong. I also halved the size of the map. Also, it contains not my best drawing...

Using these guidelines, I made two oceanic current maps for Nuelan. One is for the world rotating like the Earth, the other is for rotating opposite Earth. The white arrows show the direction of equatorial rotation. The reddish lines show the warm currents while the cyan lines show cool currents. Some of the cool currents do not change regardless of rotation due to land mass constriction at the poles.

Some more helpful information:
1) Region between 30°N to 30°S, prevaling atmospheric flow will be opposite direction of world's rotation.
2) Regions between 30° and 60°, both north and south, prevaling atmospheric flow will be same direction of world's rotation.
3) In both polar regions, prevaling atmospheric flow will be opposite direction of world's rotation.

If I have made any serious mistakes, then I hope the good folk here will correct me, please.

Hope this helps.

rmfr

Attached Thumbnails

Perhaps imagination is only intelligence having fun. - Albert Einstein

A good friend will come down and bail you out of jail. A best friend will be in jail with you and say, "Dude, we screwed up."

Thanks for all the helpful information and maps! They really help my understanding of how all this works. So basically, no matter what I do, then the circled region in the original map WILL be a tropical/desert-covered area?

How much does the rest of the world's climate matter? Given a generally earth-like situation, arakish's (amazing!) work could be a fair representation of 'plausible fiction'. But if you dial the axial tilt, distance from sun, cloud cover, amount of icecaps & continental glaciation up and down, you could probably get any small area *exactly* how you like. The rest of the planet might shift uncomfortably toward frozen, or desert, or what-have-you.

Arakish, the way those currents swirl seems reasonable. Especially since the continent blocks global flow, those three small seas to the east of the desired Europe-like area probably are very warm, self-circulating hot-tubs. Overall though, there could be some circulation that gets the Europe Analogue Isthmus some cooling, some rain without being a jungle, etc. Prevailing surface winds drive a lot of the surface currents, along with coriolis forces and the fact that these inconvenient continents generally get in the way :-). Maybe a judicious application of the pseudoscience of the wind tutorial I've started could "justify" appropriate climate.

Another consideration is just how stable do you want Nuelan's climate to be, over time? If it wobbles a bit on its axis, or if its sun is a little variable, you could pick your desired point on a cycle of cooling... glaciation... warming... desertification... repeat.

The rest of Neulan is allowed to be almost desert/desert areas, that would actually fit quite well with the storyline that I have in mind. And in regards to climate stability.. I suppose I could, how long would those cycles last though? The game I'm building is set in a slighty futuristic timeline, in a world thats economically and culturally collapsing, and that has been ravaged by the careless human race, so maybe an added aspect of sudden desertification or whatnot could add an interesting spin.

But I'll take a look at that wind tutorial then, I'm willing to do anything to get this to work.